Dodge Ram Truck 1500-2500-3500. Manual — part 1295

•

Tighten bolts 1A - 1J to 54 N·m (40 ft. lbs.)

•

Tighten bolts 1 - 8 to 7 N·m (5 ft. lbs.)

•

Turn bolts 1 - 8 an additional 90°.

•

Tighten bolts A - E 27 N·m ( 20 ft. lbs.).

8. Measure crankshaft end play.

9. Install the connecting rods and measure side clearance (Refer to 9 - ENGINE/ENGINE BLOCK/PISTON & CON-

NECTING ROD - STANDARD PROCEDURE).

10. Install oil pump (Refer to 9 - ENGINE/LUBRICATION/OIL PUMP - INSTALLATION).

11. Install the engine (Refer to 9 - ENGINE - INSTALLATION).

BEARINGS - CRANKSHAFT MAIN

STANDARD PROCEDURE

MAIN BEARING FITTING

SELECT FIT IDENTIFICATION

The main bearings are “select fit” to achieve proper oil
clearances. For main bearing selection, the crankshaft
position sensor target wheel (2) has grade identifica-
tion marks stamped into it. These marks are read from
left to right, corresponding with journal number 1, 2, 3,
4. The crankshaft position sensor target wheel is
mounted to the number 6 counter weight (1) on the
crankshaft.

INSPECTION

Wipe the inserts clean and inspect for abnormal wear patterns and for metal or other foreign material imbedded in
the lining. Normal main bearing insert wear patterns are illustrated.

Inspect the back of the inserts for fractures, scrapings or irregular wear patterns.

Inspect the upper insert locking tabs for damage.

Replace all damaged or worn bearing inserts.

MAIN BEARING JOURNAL DIAMETER (CRANKSHAFT REMOVED)

Remove the crankshaft from the cylinder block (Refer to 9 - ENGINE/ENGINE BLOCK/CRANKSHAFT - REMOVAL).

Clean the oil off the main bearing journal.

Determine the maximum diameter of the journal with a micrometer. Measure at two locations 90° apart at each end
of the journal.

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ENGINE - 3.7L - SERVICE INFORMATION

DR/DH

The maximum allowable taper is 0.008mm (0.0004 inch.) and maximum out of round is 0.005mm (0.002 inch). Com-
pare the measured diameter with the journal diameter specification (Main Bearing Fitting Chart). Select inserts
required to obtain the specified bearing-to-journal clearance.

Install the crankshaft into the cylinder block (Refer to 9 - ENGINE/ENGINE BLOCK/CRANKSHAFT - INSPECTION).

Check crankshaft end play.

CRANKSHAFT MAIN BEARING SELECTION

Crankshaft Marking

JOURNAL SIZE

SIZE mm (in.)

9

R

9

Size

63.488 - 63.496 mm
(2.4995 - 2.4998 in.)

9

S

9

Size

63.496 - 63.500 mm (2.4998 - 2.4999 in.)

9

T

9

Size

63.500 - 63.504 mm (2.4999 - 2.501 in.)

9

U

9

Size

63.504 - 63.512 mm (2.5001 - 2.5004 in.)

Bearing size

Bearing Code

Size

Application

Upper Bearing

A

.2.443 - 2.447 mm

Use with crankshaft size

9

R

9

(.0961 - .0963 in.)

B

2.439 - 2.443 mm

Use with crankshaft

9

S, T

9

(0.960 - .0961 in.)

C

2.435 - 2.439 mm

Use with crankshaft

9

U

9

(.0958 - .0960 in.)

Lower Bearing Main

9

1

9

and

9

4

9

9

1

9

2.441 - 2.447 mm

Use with crankshaft

9

R, S

9

(.0961 -.0963 in.)

9

2

9

2.435 - 2.441 mm

Use with crankshaft

9

T, U

9

(.0958 - .0962 in.)

Lower Main Bearing

9

2

9

and

9

3

9

9

3

9

2.429 - 2.435 mm

Use with crankshaft

9

R, S

9

(.0956 - .0958 in.)

9

4

9

2.423 - 2.429 mm

Use with crankshaft

9

T, U

9

(.0953 - .0956 in.)

Bearing Clearances

Main

9

1, 4

9

Crankshaft

9

R

9

.004 - .034 mm ( .00015 - .0013 in.)

Crankshaft

9

S

9

.004 - .030 mm ( .00015 - .0011 in.)

Crankshaft

9

T

9

.006 - .032 mm (.0002 - .0012 in.)

Crankshaft

9

U

9

.002 - .032 mm (.00007 -. 0012 in.)

Main

9

2, 3

9

Crankshaft

9

R

9

.016 - .046 mm (.0006 - .0018 in.)

Crankshaft

9

S

9

.016 - .042 mm (.00062 - .016 in.)

Crankshaft

9

T

9

.018 - .044 mm (.0007 - .0017 in.)

Crankshaft

9

U

9

.014 - .044 mm (.0005 - .0017 in.)

1. Service main bearings are available in four grades. The chart below identifies the four service grades available.

DR/DH

ENGINE - 3.7L - SERVICE INFORMATION

9 - 2103

SEAL - CRANKSHAFT OIL - FRONT

REMOVAL

1. Disconnect negative cable from battery.

2. Remove accessory drive belt (Refer to 7 - COOL-

ING/ACCESSORY

DRIVE/DRIVE

BELTS

-

REMOVAL).

3. Remove A/C compressor mouning fasteners and

set aside.

4. Drain cooling system (Refer to 7 - COOLING -

STANDARD PROCEDURE).

5. Remove upper radiator hose.

6. Disconnect electrical connector for fan mounted

inside radiator shroud.

7. Remove radiator shroud attaching fasteners.

NOTE: Transmission cooler line snaps into shroud
lower right hand corner.

8. Remove radiator cooling fan and shroud (Refer to

7

-

COOLING/ENGINE/RADIATOR

FAN

-

REMOVAL).

9. Remove crankshaft damper bolt.

10. Remove damper using Special Tools 8513 Insert

and 1026 Three Jaw Puller (2).

11. Using Special Tool 8511 (1), remove crankshaft

front seal.

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ENGINE - 3.7L - SERVICE INFORMATION

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INSTALLATION

CAUTION: To prevent severe damage to the Crank-
shaft, Damper or Special Tool 8512, thoroughly
clean the damper bore and the crankshaft nose
before installing Damper.

1. Using Special Tool 8348 and 8512 (2,3), install

crankshaft front seal.

2. Install vibration damper (Refer to 9 - ENGINE/EN-

GINE BLOCK/VIBRATION DAMPER - INSTALLA-
TION).

3. Install radiator cooling fan and shroud (Refer to 7 -

COOLING/ENGINE/RADIATOR FAN - INSTALLA-
TION).

4. Install upper radiator hose.

5. Install A/C compressor and tighten fasteners to 54

N·m (40 ft. lbs.).

6. Install accessory drive belt refer (Refer to 7 -

COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).

7. Refill cooling system (Refer to 7 - COOLING -

STANDARD PROCEDURE).

8. Connect negative cable to battery.

SEAL - CRANKSHAFT OIL - REAR

DIAGNOSIS AND TESTING - REAR SEAL AREA LEAKS

Since it is sometimes difficult to determine the source of an oil leak in the rear seal area of the engine, a more
involved inspection is necessary. The following steps should be followed to help pinpoint the source of the leak.

If the leakage occurs at the crankshaft rear oil seal area:

1. Disconnect the battery.

2. Raise the vehicle.

3. Remove torque converter or clutch housing cover and inspect rear of block for evidence of oil. Use a black light

to check for the oil leak:

a. Circular spray pattern generally indicates seal leakage or crankshaft damage.

b. Where leakage tends to run straight down, possible causes are a porous block, camshaft bore cup plugs, oil

galley pipe plugs, oil filter runoff, and main bearing cap to cylinder block mating surfaces. See Engine, for
proper repair procedures of these items.

4. If no leaks are detected, pressurized the crankcase as outlined in the section, Inspection (Engine oil Leaks in

general)

CAUTION: Do not exceed 20.6 kPa (3 psi).

5. If the leak is not detected, very slowly turn the crankshaft and watch for leakage. If a leak is detected between

the crankshaft and seal while slowly turning the crankshaft, it is possible the crankshaft seal surface is damaged.
The seal area on the crankshaft could have minor nicks or scratches that can be polished out with emery cloth.

DR/DH

ENGINE - 3.7L - SERVICE INFORMATION

9 - 2105